Butter manufacturing means and method



April l2, 1949. H. c.HoRN|-:MAN Erm. 2,466,895

A BUTTER MANUFACTURING MEANS ND METHOD l l Original File Dec. 13, 1941 2Sheets-Sheet 1 April 12,1949 H. c. HORNEMAN ET'AL 2,466,895

BUTTER MANUFACTURING MEANS ANI) METHOD original Filed Dec. 1s, 1941 2sheets-sheet 2 Patented pr. l2, 1949 UNITED STATES PATENT OFFICE BUTTERMANUFACTURING MEANS AND METHOD Original application December 13, 1941,Serial No.

Divided and this application November 2, 1945, Serial No. 626,234

18 Claims.

The invention relates generally to processes and apparatus for thecontinuous manufacture of butter and it also has particular relation toa method of and apparatus for developing true butter characteristics,such as texture, in. butter made according to such continuous processes.

Substantial progress has been made vin recent years in the developmentof continuous butter manufacturing processes. The primaryobject of thisdevelopment has been to overcome the diculties and objectionsassociatedwith the commonly recognizedprior art methods of makingbutter, which involve the churning of large batches of cream intobutter. With-the exception of the increased scale on which buttermanufacturing operations by the prior art or batch method were carriedout, the prior art method of manufacturing butter on a commercial scaleor otherwise bychurning remainedessentially the Y same as that used bysmall dairy men and housewives from time immemorial.

Shortly after the advent of the production or manufacture of butter onan appreciably large commercial scale, it became apparent that a greatadvantage may be attainable by producing butter by a continuous process,as distinguished from the generally, accepted prior art batch churningmethod.

It is a recognized principle of production engineering that where aproduct is to be produced in large quantities on a commercial scale acontinuous process offers certain inherent advantages over theadvantages inherent in an intermittent or batch type process. Some ofthe principal advantages of the continuous manufacture of a product by acontinuous process are that the continuous process enables theattainment of an appreciably greater production rate in relationto theamount of equipment involved, and, what may be of even greaterimportance, a continuous process of manufacturing a product permits themaintenance of a high degree of standardization and control of theproduct. Thus, a continuous process of manufacturing butter permits themanufacture of butter having improved qualitycharacteristics anduniformity and also permits such .more desirable production at a reducedcost per unitof product. l

One of the greatest difficulties encountered in the development of asatisfactory and acceptable continuous butter manufacturing process wasthe difculty of obtaining a final ultimate butter product whichpossessed texture and other desirable characteristics which comparedfavorably to similar characteristics present in high quality 2 butterexpertly manufactured by the use of the conventional, intermittent orbatch churning process. Although several continuous processes for themanufacture of butter which may have been suggested and developedwherein a butterflike product could be produced which, upon analysis,appeared to have a chemical composition corresponding to that of buttermanufactured by the intermittent or batch process, the physical aspectsof such butter products manufactured by continuous processes heretoforesuggested in the prior art were, however, fundamentally different fromthe corresponding physical aspects or characteristics present in buttermanufactured by the conventional batch churning method. Insofar as weare aware, it was not possible heretofore to produce a butter product bya continuous method or process in which the butter thus producedpossessed a true butter texture and other physical and chemical buttercharacteristics with which the public is thoroughly familiar, and whichthe public associates with good butter. The consuming public has becomeso accustomed to using butter having a texture of the type whichcharacterizes the butter manufactured by the intermittent or batchchurning process that the absence of such texture, as well as otherphysical properties, in butter manufactured by heretofore knowncontinuous processes constituted one of the major dimculties in thedevelopment of a satisfactory con` tinuous process for the manufactureof butter.

One of the principal objects of our invention, therefore, generallystated, is the provision of an apparatus and method of developing a trueand natural butter texture in butter products made according to theimprovedcontinuousbuti-- termaking process, hereinafter described. Theinvention is particularly well adapted for use in connection with thecontinuous method of manufacturing butter, set forth in our applicationfor United VStates Letters Patent Serial Number 368,750, filed December6, 1940, and entitled Butter process," now Patent No. 2,423,834, grantedJuly'15, 1947. j

This application is a division of our parent application Serial Number422,798, entitled Butter making means which was filed December 13, 1941,now Patent No. 2,395,051.

According to one aspect of our invention, a product having thecomposition of butter, but not having a true or natural Abutter texture,may be forcibly fed through a series of restricted orlces which may bedisposed at spaced apart 1ntervals in a conduit and a true butter4texture audace The texturating :apparatus is described andl claimed inour parent application Serial No. 422,798.

According to another aspect of our invention, a product having thecomposition of butter may be 'converted into butter by forcibly passingthe same through a chilling or freezing unit, and a further working ortexturating unit. l

Other aspects of the present invention pertain to the processing of thecream, which is used to produce the product having the composition ofbutter, prior tothe conversion of the product into butter, and to theaspect of providing certain physical characteristics in the final butterproduct by the introduction of suitable quantities of gas into theproduct ha'ving the composition of butter while it is being processedinto butter. Accordingly, a further object of the present invention isto provide the necessary means and method for the conversion of theproduct having the composition of butter into butter possessing thehighly desirable qualities and characteristics of expertly made butter.

For a more complete understanding of the nature and scope of ourinvention, reference may be had to the following detailed descriptionthereof, taken in connection. with the accompanying drawings in which:

Figure 1 is a flow diagram of a plant wherein cream may be manufacturedinto butter by a continuous process of operation according to thepresent invention, involving the pasteurlzing unit, the centrifugingunit, blending unit, chilling unit and the texturating unit;

Figure 2 is a side elevational, fragmentary View,

showing the details of construction of the freezing unit forming a Dartof the plant shown in Figure 1 of the drawings; l

Figure 3 is an enlarged,.fragmentary, vertical. sectional view, takenthrough one of the sections between-.the different sections of thetexture developer illustrated in Figure 1 ofthe drawings, and showingthe details of one of `the texture developing orifices provided therein;

Figure 4 is atop plan view of the orifice-pro- `viding disk in the pipelconnection shown in'Fig- 111e.3 of the drawings;

Figure-5 is a viewsimilar to Figure 2 of the drawings of`r a modifiedform of freezing unit adapted to intersperse or introduce a non-toxic,

. smoothness-imparting gas-intoa product having the composition ofbutter as it is chilled and ,solidified in the freezing unit.

`Inthe manufacture of butter by the improved continuousprocess, it isfirst-necessary to obtain concentrated milk fat with the fat portionthereof in thecontinuous phase. In cream, which is the raw materal'usedin the manufacture of butter,

I 'the milk fat portion of the cream is in the dispersed or suspendedphase, while the water portion of the'cream is-in the continuous` phase.

` Although'there are several possible processes by which thephase'in-cream may be reversed so I as to obtain the milk fat portion thereof.in concentratedfor'm with the milk fat portion Vin the continuousphase,the process described in our above mentioned parent application forUnited States Letters Patent Serial No. 422,798, and our trated processof obtaining concentrated milk fat with the fat portion thereof inthecontinuous phase, and also as disclosed in the above mentionedapplications, iscombined with further process steps and apparatus forthe conversion of a product having the composition of butter into butterand for texturating or developing a suitable butter texture in thebutter manufactured according to this invention to ultimately secure ahigh quality butter product.

It will, however, be understood that the texture developing aspect ofthev present invention is not limited solely to use in connection withthe milk fat concentrating process described in this application and inour prior application for United States Letters Patent Serial No.368,750, as is clearly pointed out in our parent application Serial No.422,798.

Referring again to Figure 1 of the drawings, cream having a milk fatconcentration of approximately percent to 40 percent is warmed to atemperature of approximately 90 F. to 100u F. in a pre-warming vat I0.In the event that neutralization of the cream is desired, the cream maybe neutralized, for example, in the prewarming vat i0 in accordance withthe generally accepted practice of the butter making art. From the vatI0, the pre-warmed cream is pumped by pump II through conduit I2 intothe lter I3. Steam under a pressure of approximately 90 to 100 poundsper square in oh is introduced into the conduit I2 from the steam supplyline I4 connected therewith, as shown. introduction of steam intoconduit I2 serves to further warm or heat the cream as it passes throughthe conduit I2, so that when the cream enters the filter I3 thetemperature thereof is approximately'135" F. The cream, after passingthrough the lter I3, is conducted through a pipe 40 line I5 into a flashtype pasteurizer unit I8, which pasteurizer unit may, if desired, be ofthe wellknown Jensen type. Steam is introduced into the conduit I5 froma steam supply line I1 associated therewith and is mixed with thefiltered vcream so that the lteredcream, as it enters the lower portionof the pasteurizer I6, will have a .temperature of approximately 150 F.to .160 F.

, and in the well known .Jensen type pasteurizer.

conduit I8 into a supply or storage tank .20, from l which, in turn, itisdelivered to a zone of subatmospheric -or reduced pressure or vacuumfor further steam vacuum treatment in the vacuum- -steam pasteurizer 23.The pasteurized -cream, vwhich has been discharged from the pasteurizerunit I6, is preferably withdrawn from the supply unit 20 through conduit22 and at a temperature of approximately F. to 190 F. into the vacuumpasteurizer 23. The vacuum pasteurizer 23 may be of various types wellknown in the art. For the purpose of this application, the vacuum steamtype pasteurizer illustrated in Figure 1 of the drawings is similar indetail to the vacuum steam type pasteurizer disclosed in United StatesLetters Patent No. 2,022,420. The pressure in the vacuum steampasteurizer 23 is a reduced or subatmospheric pressure and is ordinarilymaintained at a vacuum of approximately 25 to 26 Such i ananas inches ofmercury so that the temperature in the chamber 23 will be approximately130 F. Steam under a pressure of approximately 90 pounds per square inchis introduced into the lower portion of the vacuum steam pasteurizer 23,through a number of steam pipes or orifices 24, associated with thechamber 23, as illustrated in Figure 1 of the drawings. The steam thusintroduced into the chamber 23 comes into direct contact .with the creamwhile the cream is under a reduced pressure. The desired pressures andtemperatures are readily maintained in the vacuum chamber 23 bywithdrawing water vapor and other volatile materials and gases from theupper portion o1' the chamber 23 at station 25, by means of anyconventional vacuum-producing apparatus, such as a vacuum pump (notshown).

The treated cream which, in substance, has neither lost n or gained anymoisture content collects in the lower portion of the chamber 23 and itis pumped therefrom by means of the pump 26 through the pipe line 21into a centrifuging separator 30. The temperature oi the cream in theseparator 30 is approximately 125 cent milk fat, with the milk fatportion thereof in the continuous phase. The major portion of the skimmilk and protein, which form an appreciable portion of the raw milk orcream, is separated in the centrifuging separator 30 from the portionYof the raw milk or cream containing the highly concentrated milk fat inthe continuous phase and is discharged from the separator 30 through thespiggot 3l. The highly concenincoming mixture being introduced into thevfreezer from the conduit 43. and ln that manner is forced through thetexture developer or texturator unit, identified generally by thenumeral 43, in which texturator unit the texture or physical propertiesof the butter is improved and developcd. The butter. upon leaving thetexturating unit 46, is delivered to a'packaging machine.

sures mentioned above asexamples in connection with the description ofthe preferred method of practicing the aspect of ourjinventionpertaining to the process of manufacturing butter, together with theoperation of the vacuum pasteurizer 23 and the centrifugal separator 30,are illustrative of typical operating conditions. Obviously, certainother temperatures and pressures, not specifically mentioned above, maybe used whenl'necessary depending, of course, upon other specific andrelated conditions. The change in the cream during the vacuumsteamtreatment above described is not fully understood. It would appear thatthe subjection of the cream to the sub-atmospheric or reduced pressureconditions within the-'chamber 23 produces an expansion of the cream andthat the action of the high pressure steam, as aforementioned, whencoming into direct contact with the expanded cream, modies the milkfatglobules in such a fashion that the milk fat may be sepal rated into thecontinuous phase` when subjected trated milk fat product, which isdischarged from the separator through conduit 32, passes through theconduit into the storage tank or vat 33. From the. vat 33, the emulsionor mixture containing the milk fat in the continuous phase and still ina liquid state is pumped by pump 36 through interconnected pipes 35 and36 into a mixing chamber or unit 31. Suitable quantities of controlledaqueous solution of salt. water and starter flavor, etc., may be pumpedin at a predetermined rate by pump 4! from the supply Vat or reservoir40 through conduit 42 and conduit 36 into the mixing chamber 31, whereinthe controlled aqueous solution is thoroughly mixed with the incomingmilk fat mixture being supplied to the mixing chamber from the vat 33.

The resulting mixture, having the composition of and intended for use informing butter, is discharged from the mixing chamber 31 through conduit43, and upon discharge from the mixing chamber 31 the discharged mixturecontains at least percent of milk fat. Pump 44 in the conduit i34 forcesthe standardized milk fat mixture being discharged from the mixingchamber 31 to and through the freezer or chilling unit 45. In thefreezer or chilling unit 45, the liquid butter-forming mixture issolidified or continuous phase indicates thatk the complexy 'protein-fathull ormembrane surrounding the to the centrifuging action in theseparator 30. It would also appear that other desirable results may beobtained when the cream, upon entering the zone of sub-atmospheric orreducedpressure in the chamber 23, has first been pre-heated to atemperature greater than the temperature of the saturated steam at thereduced pressure as used inthe chamber 23; Th fact that the milk fatportion of the mixture or emulsion, discharged through conduit 32 fromseparator 30, is in the milk fat globules is modified physically orchemically or both by the combinedva'cuum and steam treatment in thechamber 23. 1t will, of course, be understood, however, vthat thepresent invention is not to be limited by any particular theoreticalexplanation as,contained, for example, in this paragraph. f

The addition of a controlled amount of Water and the addition of thedesired amount of salt and flavor starter to the concentrated milk fatin the mixing unit 31 enables the attainment of a more uniform and finedispersion of the water, salt or brine in the milk fat to be convertedinto butter, with the result that the butter produced from such. amixture possesses improved physical properties, such, for example, astexture. The specific amount of water or aqueous solution added' to themilk fat mixturepriorto the conversion into butter varies with the`percentage of milk fat in concentratedform in the vat 33, in which vatthe milk fat concentration normally varies between percent and 95percent. The

quantlty of water or aqueous solution added to in such a manner and tosuch an extent that least 80 percent of milkfat.A

The new and improved process of continuously manufacturing butterproduces a more stable butter which, at least to some extent, may beattributable to the fine dispersion of water or brine throughout thecontinuous milk fat phase and to the low protein content of the milk fatconverted into butter. In this latter connection, it should be notedthat substantial proportion of the nitrogeneous protein material, whichcomprises one of the bacterial foods normally found in butter, isseparated from the milk fat in the centrifugal separator 3D. The new andimproved process of manufacturing butter also enables the production ofa more uniform butter product, due to the removal of the original waterand water-soluble materials in the cream prior tothe conversion of themilk fat content thereof into butter. Such an advantage is secured byseparating the original non-fat materials from the cream and replacingthem with controlled aqueous solutions or starter mixtures free fromundesired characteristics and free from contamination That suchadvantages must result will, of course, be obvious to those skilled inthe art.

An additional advantage of the new and improved process of continuouslymanufacturing butter resides in the elimination from the process of thechurning operation used in all batch or intermittent churning operationsand carried out even today, for the most part, in bacteriacontaminatedwooden churns.

In the specifications and claims, the term starter refers to starterculture. These cultures are well-known in the art of buttermaking andserve as flavor constituents or means for securing the desired iiavor inbutter. Likewise, in the specifications and claims, the term creamrefers to the product ordinarily understood to constitute cream and inwhich the milk fat portion thereof is in the dispersed phase, i. e.,dispersed as an emulsion in a continuous phase of non-fat milk liquids.

Referring to Figure 2 of the drawings, it win be' seen that the freezeror chilling unit 45 comprises an inner cylinder 50, in which thebutter-forming mixture from the mixing tank 31, as shown in Figure 1 ofthe drawings, is chilledand solidified. A brine or refrigerant jacket 5iis disposedaround the inner cylinder 50, -s`o thata `refrigerant mayforming mixture into the cylinder 50. The rightthe concentrated milk fatis accurately controlled y I l hand or .discharge head for the cylinder50 is provided with a jacketed outlet connection, through which thechilled and solidified mass or material may be delivered from theinterior4 of the cylinder 50 to the texturator or texture developingunit 45. Central openings are provided through each of the cylinder headunits 55 and 56, so as to accommodate a hollow shaft E0, which flstenslongitudinally through the freezer unit 45 and more specificallycentrally through the chamber 50. The shaft is journaled in the heads 55and 56 in a conventional manner so as to provide suitable bearings forthe shaft. A pair of stuffing boxes 6| and 52 are provided on the outerfaces of each of the cylinder heads 55 and 56, whereby to secure iiuidtight joints or seals about the rotatable shaft 60.

A helical screw or agitator is carried on the shaft 60 within thefreezing chamber 50, as clearly indicated in Figure 2 of the drawings.The function of the screw 65 is to scrape the chilled butter-formingmixture from the refrigerated inner surface of the chamber 50 wherein itis solidified and also to aid, insofar as possible, in forcibly feedingthe butter-forming material from the left or intake end of the cylinder50 to the right or discharge end of the cylinder 50 to thereby aid incompleting the passage of the material through the freezer unit 45. Thescrew 65 also acts as an agitator for the partially solidified andpartially liquid butter-forming mass in the cylinder 50, particularly.during the period of time during which the material being processed inthe cylinder 50 is in a liquid state. A pulley 66, keyed to theleft-hand end of the shaft 60 beyond the stufling box 6l, provides thenecessary means for rotatably driving the shaft 60 and the associatedscrew 65 carried thereon.

The shaft 6U is preferably tubular or hollow, so that a tempering mediumsuch, for example, as hot water may be circulated therethrough for thepurpose of melting off solidified butter-forming mass or material whichmay be frozen or adhere to the shaft 60 or on the helical screw 65. Thisfeature of the construction is important in connection with cleaning ofthe frezer unit 45, for the reason that it permits substantially all ofthe mixture in the cylinder 50to be discharged from the rright-hand ordischarge end thereof through the outlet connection 58.

Aspreviously pointed out, thejacketed outlet connection 58 of thefreezer unit 45 is connectedin turn with the novel texturator or texturedeveloping unit'46, as clearly illustrated in Figureland Figure 5 of thedrawings. The partic- 'ular texture developing unit 46, as shown in thedrawings, is preferably made in four sections,

each of which sections comprises an inner tube frig'erant from thefreezing unit 45. jIt has been The inner cylinder 50 ofthe freezing unit45 .is closed at its opposite ends by a parof heads 55 and 56 connectedin flange to flange relationship therewith in the manner shownin Figure2 p of the drawings. Thejhead 55, attached to the left-hand orintakeendof the cylinder 50, has

an inlet opening or lconnection 51 integrally 'formed as a part thereofand to which the con-l duit 43 is connected for supplying the butterorconduit through which the butter to be texturated is fed, and an outerjacket to enablethe circulation of a -heat exchange medium, such aswater, in heat exchange relation with' the inner tubeof the texturator46. One of the connections between the four sections of the texturatoris illustrated in detail in Figure 3 of the drawings. As there shown,the lower end 'H of the inner pipe 10 of the upper section of the tex-.turator is counterbored so as to 4fit over the upper end' l2 of theinner pipe 'l0 in the next lower section. A `disk element or member 14,shown in plan view in Figure 4 of the drawings, is centered between theinner-fitting pipe ends ll and 12,' as shown in Figure 3 of thedrawings. The disk member 14 is provided with a restricted slotthe useof the illustrated procedure in the practice of the present invention,the butter being texturated is forced through the slot-shaped orifice asit is fed or forced through the texturator or texture developer 46. Thedisk member 1li is so machined and designed that it is generallycup-shaped with a short portion formed on the bottom thereof to vbefitted into the upper end of the pipe 12 with the annular shoulderabutting Aagainst the face of the upper end` of the pipe 12. The upperedge of the disk member 14 is fitted accurately against and fiush with ashoulder formed in the lower end` of the counterbored pipe 1I, asindicated at 16. The inside of the disk member 14 is preferably'smoothlycupped and rounded so that there may be no sharp corners in which buttermay accumulate or collect and be retained during the operation of themechanism.

The upper pipe 10 is surrounded by a jacket section 80, having an insetskirt 8l integrally formed on the lower end thereof, and which tsaccurately within the upper end of the lower jacket section 80surrounding the lower inner pipe' 1U. The jacket sections 8U areprovided with opposing integral flanges 83 and 8d, which are separatedby a gasket member 85. A number of swingable or hinged clamps 86 arecarried on the lower jacket section 80 below the flange Sli and areadapted to swing up and around the flanges 83 and 8d when in operativeposition, as clearly shown in Figure 3 of the drawings. A set screw 81,having a wing nut head .is provided in a threaded hole in each of theclamp members 86 to enable the tightening thereof against the upper faceof the flange 83, as is shown in Figure 2 of the drawings. Obviously,any suitable number of clamps 86, such as 3, 4 or more, may be providedas appears necessary.

Certain other types of' lconnections between the different sections ofthe texturator cr texture developing unit 6 may obviously be used, andthe design illustrated in FigureB of the drawings represents o'nly onesatisfactory design whereby the sections may be conveniently and readilytaken apart for cleaning, and reassembled.

During the use of the texturating unit 36 incidental to the practice ofthe improved process of manufacturing butter, as herein described, warmwater may be supplied into the upper end of the space between the innertubes of the texturator and the jacket 80.

This Warm water may be supplied through the annular passageway formed inan inlet connection 90 and may be withdrawn from the lower sectionthrough an outlet or discharge pipe 9i. The inlet connection 90comprises an inner pipe 13 which communicates with the inner pipe 10 inthe top section of the texturator or texture developing unit 46, and anouter` jacket 82, which connects into the uppermost jacket section 8G.The pipe 13 is provided with a valve i9 adjacent to the inner pipe 10,as shown in the drawings. The Water supplied through the annular spacebetween the inner pipe 13 and the outer pipes 82 should preferably be atsuch a temperature and should preferably be circulated at such a ratethat the butter being texturated, which is in immediate contact with theinner pipes 10 and 12, may be slightly warmed and perhaps even melted.Such a warming of the butter in frictional engagement with the innerpipes 10 and 12 and corresponding inner pipes shaped orifice 15,centrally formed therein/n Y. ...10MV Y "of the texturator permits thebutter being texturated to slip or slide easily through the texturatingunit without any objectionable fricvtional working thereof as a resultof the engagement or contact of the butter with the inner faces of thepipes 10 and 12 and like pipes of the texturator.

Disk members, -similar to the disk 14, are provided in each of the threeconnections at stations 492, 93 and 94, between 4the four sections ofthe texturator 4B, as illustrated in Figure 2 of the drawings. Each ofthe disks 14 may be provided with a restricted orifice which may be inthe shape of' a slot similar to that illustrated by the orifice 15 inFigure 4 of the drawings. Under normal conditions, it will be desirableto make the connections 92, 93 and 94 the same, so that the partsthereof, as well as the disk elements, may be interchanged.

A fourth disk element or member (not shown in particular detail) isprovided at station 95 at the lower end of the texturator or texturedeveloping unit d6, at the point Where the lower section of thetexturator i6 connects with anv outlet fitting 96. The orice or openingin the fourth disk member at the station or connection 95 may, ifdesired, be circular in cross-section instead of slot-shaped and may besomewhat smaller in net cross-section area than the cross-section 'areaof the aforementioned orifice 15 in the aforementioned disks 14 at theconnections 92, 93 and 96. For example, the slot-shaped orifice 15 inthe disk member 14 (Figure 4 of the drawings) may be 1" x 1%", While theorifice in the disk member in the connection or station 95 may be 1% ofan inch in diameter. The pressure applied to the butterforming mixtureby the delivery pump till, together with the action of the screw 65 inthe freezer unit 45, serves to forcibly feed thesolidied butter to andthrough the texturator or texture developing unit G6. When the butterleaves the freezer t5 it is in the form of a somewhat brittle, waxymass, which is oily to the taste, having in mind, of course, that themass is formed of a chilled fat product. As this mass is forced throughthe spaced orifices of reduced size provided in the texture developingunit or texturator 46, while this chilled butter product passesrelatively slowly from orifice to orifice, a true butter texture isdeveloped in the butter. The reason for and nature of the reaction whichtakes place in the butter passing through the texturator is not fullyunderstood. In any event, however,

butter having a very desirable texture is developed from what was asomewhat brittle, waxy mass or product when the butter was dischargedfrom the freezing unit d5.

In certain instances, it may be desirable to intersperse or inject anon-toxic, smoothness-imparting gas into the liquid butter-formingmixture as it is being solidied or chilled in the freez ing unit 45. InFigure 5 of the drawings, there is illustrated `a modified freezingunit, generally identified by the numeral |00, inwhich an inert gas,such as nitrogen, may be interspersed or injected into thebutter-forming mixture as it is being solidified therein. In general,the construetion of the freezing unit |00 may closely follow that ofthebefore-described freezing unit 45, as illustrated in Figure 2 of thedrawings. However, the connection IDI is provided on the freezing unitH00, leading into the lower left-hand' end of the receiving endof theinner freezing chamber, through which connection IDI an inert gas, such,for example, as nitrogen, may be injected intothe interior of thefreezing chamber. The connection |||I is connected with one side of aT-fitting |02 while the gas inlet pipe |03, having a valve therein,connects with the opposite side of vthe fitting |02. A pipe line |05,having a valve |00 therein, is connected into the left-hand side of theT-fitting |02, and may be used from time to time as desired as an inletfor supplying warm water or steam into the freezing chamber incidentalto the cleaning thereof.

In the modified freezing chamber, illustrated in Figure 5 of thedrawings, .there is shown a modified form of the helical screw oragitator, identified with the numeral H0. The modified helical screw H0is preferably mounted on the tubular drive shaft |09, extendinglengthwise or longitudinally through the freezer |00. The helical screwH0 is comprised of a number of short blades III, each of which iscarried on a hub member H2, secured to the drive shaft |09. The bladesII| are spaced a short distance apart one 'from another, but in theirgeneral outline and manner of arrangement forma helical screwcorresponding generally to the helical screw 65 ofthe freezing unitillustrated in Figure 2 of the drawings. 'Ihe spacing between the bladesI I I increases the chopping or agitating action of the screw IIII and'serves to more'uniformly intern sperse the inert gas entering thefreezing chamber by way ofrthe inlet connection IUI through thebutter-forming mixture as. it is being solidified within the freezingunit I 00.

Obviously, certain further changes in the apparatus hereinbeforedescribed may suggest themselves to those skilled in the art anddifferent em.. bodiments of the invention pertaining to the apparatusfor the continuous manufacture of butter may be made without departingfrom the scope of our invention. It is intended that all mattersdescribed hereinbefore, pertaining to the improved process andapparatus, or as illustrated in the accompanying drawings, should beinterpreted as illustrative only-of applicants invention.

The invention is hereby claimed as follows:

1. Means for converting a butter-forming mixture of liquid milk fat andwater, which may include salt and flavor starter in desired amounts,into butter which comprises, in combination, freezer means wherein theliquid butter-forming mixture may be solidified, texture developingmeans wherein the solidified mixture may be given a true butter texture,said texture developing means comprising, conduit means with orificemeans therein, and means for moving the butterforming material in itsdifferent stages of conversion through the various parts of theconverting means.

2. Means for converting a butter-forming mixture of liquid milk fat andwater, which may also include salt and flavor starter in desiredamounts, into butter, which comprises, in combination, a combinedfreezer and gas interspersing unit wherein the liquid butter-formingmixture-may ybe solidified and have non-toxic smoothness-imparting gasinterspersed therethrough, texture developing means wherein thesolidified mixture may be given a true butter texture, said texturedevelopingfmeans comprising, conduit means with orice means therein, andmeans for moving the butter-forming material in its different stages ofconversionthrough the various parts of the converting means.

3. In a continuous process of making butter, the method of convertingabutter-forming mixture of liquid milk fat and water, which may also 12include salt and flavor starter, into butter which comprises,solidifying the liquidbutter-forming mixture into a brittle waxy mass,and developing 'a true butter texture in said brittle waxyv mass byforcing it through restricted orifice means.

4. In a continuous process of making butter, the method of converting abutter-forming mixture of liquid milk fat and water, which may alsoinclude salt and flavor starter in desired amounts, into butter whichcomprises, solidifying the liquid butter-forming mixture into a brittlewaxy mass while' interspersing a non-toxic smoothness-lmparting gas'therethrough, and developing a true butter texture in said brittle waxymass by forcing it through restricted orifices.

5. A continuous butter making process which comprises, subjecting creamcontaining milktfat in the dispersed phase to reduced pressure,subjecting the cream while at the reduced pressure t'o the direct actionof steam. concentrating the milk fat by subjecting the treated creamwhile at a temperature above the melting point of said fat to acentrifuging action, separating the' concentrated .milk fat inthecontinuous phase from vthe other constituents of said cream, mixing Ythe milk vfat withwater and-desired amounts of salt and vflavor vstarterin such proportions as to provide a butter-forming mixture, solidifyingthe liquid butter-forming mixture into a brittle waxy mass, anddeveloping a true butter texture in said brittle waxy mass by forcing itthrough restricted orifice means.

6. A continuous butter making process which comprises, introducing creaminto a zone of subatmospheric pressure at a temperature substantiallygreater than the temperature of saturated steam at said pressure,subjecting the cream while at the reduced pressure to the direct actionof high pressure steam, separating out the milk fat of said cream intothe continuous phase by subjecting the treated cream while at atemperature above the melting point of said fat to a centrifugingaction, mixing the milk fat which is in the continuous phase with waterand desired amounts of salt and flavor starter in such proportions as toprovide a butter-forming mixture, solidifying the liquid butter-formingmixture by chilling so as to convert it into a brittle .waxy mass, anddeveloping a true butter texture in said mass by forcibly feeding thesame through a series of restricted orifice openings.

7. A continuous process of making butter which comprises. introducingpasteurized cream at a temperature Aof around 175 F. to 190 F. andcontaining from about 30 percent to 40 percent milk fat in the dispersedphase into a zone of sub-atmospheric pressure, subjecting the creamwhile at the reduced pressure to the action of high pressure steam,withdrawing water vapor from said zone so as to prevent an increase insaid sub-atmospheric pressure and maintain a temperature of about 130 F.to 135 F. within said zone, concentrating the milk fat by subjecting thetreated cream while at a temperature of around F. to a centrifugingaction, separating the resulting concentrated fat containing'l i3texture in said mass by forcibly feeding the same through a series ofrestricted orices.

8. Means for converting a butter-forming mix- Ature of liquid milk fatin the continuous phase and water, which may also include salt andflavor starter in desired amounts, into butter, which comprises, incombination, a combined chillingr and water, which may include salt andavor texture developing means, means for circulating a fluid ofcontrolled temperature through said jacket means s o as to control thetemperature of the butter-forming mixture in said texture developingmeans, and means for moving the butter-forming material in its dilerentstages of conversion through the various parts of the converting means.

10. A continuous process of mak-ing butter which comprises, subjectingcream containing milk fat in the dispersed phase to reduced pressure,subjecting the cream while atv the reduced pressure to the direct actionof steam,concentrat ing the milk fat by subjecting the treated creamwhile at a temperature above the melting point of said fat to acentrifuging action, separating the concentrated milk fat in thecontinuous phase from the other constituents of said cream, mixing themilk fatwith water and desired amounts of salt and flavor starter insuch proportions as to provide a butter-forming mixture, solidifying theliquid butter-forming mixture into a brittle waxy mass Whileinterspersing anon-toxic smoothness imparting gas therethrough, anddeveloping a true butter texture'in said brittle waxy mass by,

forcing it through restricted orices.

11. A process of producing butter, comprising heating cream to at leasta milk fat melting temperature and breaking the normal milk fat in milkserum phase relation in the emulsion of the cream to produce a'mixturewherein the milk fat in milk serum phase is reversed and wherein themilk fat and milk serum portions are in unstable readily separablerelationship, separating a fraction from the destabilized creamcontaining a high concentration of milk fat in the continuous phase,adding butter composition ingredientsto the fraction containing the highconcentration of fat in amounts necessary to prodduce the desired buttercomposition therein, thoroughly intermingling the added ingredients andthe separation fraction containing the high concentration of iat,vsubjecting the thoroughly intermingled mixture to simultaneous agitationand cooling to crystallize at least a substantial partof the milk fatcontent thereof, and developing a true buttertexture in the cooledbutter by forcibly feedingthe same through a conduit includingrestricted oriice means.

milk serum phase relation in the emulsion of the cream toproduce amixture wherein the milk fat in milk serum phase is reversedand whereinthe milk fat, and milk serum portions are in unstable readily separablerelationship, separating a fraction from the destabilized creamcontaining a,

high concentration of milk fat in the continuous phase, adding buttercomposition ingredients to the fraction containing the highconcentration of fat in amounts necessaryto produce the desired buttercompositionl therein, thoroughly intermingling the added ingredients andthe separation fraction containing ,the high concentration of fat,subjecting the thoroughly' intermingled mixture to simultaneousagitation and cooling to crystallize at least a substantial part of themilk fat content thereof while interspersing a non- -toxicsmoothness-imparting gas therethrough, and developing a true buttertexture in said plastic butter mass byiorcing it through a passage 'soconstructed and arranged as to produce relal tive motion between thecrystallizedfat portions thereof. v

13. A process for producing butter from cream, comprising heating thecream to at least a milk fat melting temprature, subjecting the heatedcream to forces'eiective to break the normal milk fat in milk serumemulsion and to produce a reverse phase milk serum in milk fat mixturehaving its milk fat and milk serum portions in unstable readilyseparable relation, separating the mixture 'to produce a portion havinga high milk fat concentration, adding butter composition standardizingingredients to the portion contaning the high milk fat concentration inan amount'necessary to produce the desired butter composition therein,thoroughly intermingling the standardizing ingredients andthe separationfraction containing the high concentration of milk f at, thensimultaneously cooling and stabilizing the standardized mixture tothoroughly cool and stabilize the components thereof and to crystallizeat least a substantial portion of the milk fat content thereof whileinterspersing a nontoxic smoothness-imparting gas therethrough, anddeveloping a true butter texture in the cooled butter mass by forcing itthrough a passage including a' restricted oriiice.

14. A coordinated apparatus for the continuous production of butter,comprising, in combination, means for destabilizing a dairy productcontaining milk fat in the dispersed phase, means for separating asubstantial portion of the milk fat from the destabilized dairy productto produce a separation fraction having a high milk fat concentration inthe continuous phase, cooling and working means for simultaneouslycooling and working the separation fraction containing the highconcentration of milk fat to produce butter in which at least asubstantial portion of the milk iat is crystallized, texture developingmeans including restricted orifice means for developing a true buttertexture in the cooled butter, and connecting and circulating means forconnecting all in series in the order mentioned and for. causing thecirculation therethrough of the product being processed.

15. A coordinated apparatus for the continuous production of butter,comprising, in combination, means for destabilizing a dairy productcontaining milk fat in the dispersed` phase, means duce a separationfraction having a high milk fat concentration in the continuous phase,means for Messes. y

aration fraction containing the high concentration of milk fat toproduce butter in which at least a substantial portion of the milk fatis crystallized, texture developing means including restricted orificemeans for developing a true butter'texture in the cooled butter, andconnecting and circulating means for connecting all in series 1n theorder mentioned and for causing the circulation therethrough of theproduct being processed.

16. A coordinated apparatus for the continous production of butter,comprising, in combination, means for destabilizing a dairy productcontaining milk fat in the dispersed phase, means for separating asubstantial portion of the milk fat from the destabilized dairy `productto .produce a separation fraction having a high milk fat concentrationin the continuous phase, means for introducing predetermined quantitiesof butter composition standardizing ingredients into the separationfraction containing the high concenintermingling the standardizingingredients and thes'eparation fraction containing the high conincludingmeans having 'a restricted passage therethrough. to produce a truebutter texture therein and to facilitate ythe substantial completion ofthe major portion of the crystallization of the fat crystallizable atthe temperature to which the product was cooled.

, 18. A coordinated apparatus for continuously .producing butter,comprising the combination of means for destabilizing a dairy productcontaintration of milk fat, mixing means for thoroughly restricted.orifice means for developing a butter g texture in' the cooled product,and connecting and circulating means -for connecting all in series ingmilk fat in the dispersed phase, separating means for separating asubstantial portion of the milk fat from the destabilized dairy productto produce a separation fraction having a high milk fat content in thecontinuous phase, and cooling and agitating means for cooling andconcurrently agitating the separated portion of the dairy productcontaining the high concentration of milk fat to produce butter in whichat least a substantial portion of the milk fat is crystallized, andtexture developing means including oriiice means to receive the cooledbutter and to develop a true butter texture therein, and connecting andcirculating means connecting all in series in the order mentioned andfor causing the circulation therethrough of the product being processed.

HERMAN C. HORNEMAN. RALPH V. HUSSONG. SIDNEY N. QUAM. BERNARD W. HAMMER.

- REFERENCESV CITED The following references are of record in the illeof this patent:

UNITED STATES PATENTS OTHER REFERENCES Hunziker, The Butter Industry,"third edition, published by the author, La Grange, Illinois (1940) pages304-309.

